1. Field of Art
The present disclosure relates generally to keypads for receiving user inputs for operating electronic devices, more specifically to keypads capable of changing its configuration according to input modes of the electronic devices.
2. Description of Related Art
A physical keypad includes a set of buttons or keys each mapped to represent a different number, letter, symbol or function. The physical keypads are often used in electronic devices such as telephones, Personal Digital Assistants (PDA), mobile computing devices, and remote controllers. The physical keypads are generally designed to be functionally adapted to the specific electronic devices. To provide the necessary functional user inputs to the electronic device, the physical keypads have a set of buttons or keys arranged in a particular configuration. The physical keypad is often the main area of user interaction. Therefore, the physical keypad is often designed to be aesthetically pleasing to the user.
It is generally preferable to provide the physical keypad with a minimum number of buttons or keys. A large number of buttons or keys in the physical keypads may cause confusion to the user as to which button to press. Also, the amount of space in the electronic device that can be used for placing the physical keypads is generally limited. Therefore, in order to put more buttons or keys in the physical keypads, the size of the buttons or keys needs to be reduced. The reduced size of the buttons or keys, however, makes it harder for the user to find and press the correct button of key.
Therefore, in some electronic devices, the same button of the physical keypad is used for indicating more than one number, letter, symbol or function that differ depending on the input modes of the electronic device. Using the same button to indicate different number, alphabet, symbol or function is advantageous because the number of buttons or keys can be reduced. The buttons or keys, however, must be printed or engraved with more than one number, alphabet, and symbol. Printing or engraving more than one number, letter, or symbol on the buttons or keys is aesthetically less pleasing. Also, physical keypads using such buttons or keys, however, may cause confusion to the user because the user may become uncertain which printing or engraving indicates the correct input in the current input mode. In addition, overpopulating a button with symbols or text could eventually make it difficult to read due to crowding in a limited space.
Another input device often used is a touchscreen. The touchscreens display graphical user interface to the user as well as receiving inputs from the user through the touch of the screen by a finger or a stylus. The touchscreens are often used in electronic devices to replace or supplement the keypads. The touchscreens are also capable of displaying various types of virtual keypads on the screen. Because the virtual keypads displayed on the touchscreen can be changed depending on the input modes of the electronic device, it is possible to display only the buttons or keys associated with the current input mode of the electronic device on the touchscreens. Therefore, using the virtual keypads is more intuitive to the user and aesthetically pleasing compared to the physical keypads.
The touchscreens, however, have the disadvantage of high power consumption. The touchscreens use display devices such as liquid crystal displays (LCD) that employ backlights. The backlight consumes considerable amount of electricity. Such high power consumption is especially problematic for mobile electronic devices that use batteries. Another issue in using the touchscreen is that the touchscreen provides limited or no tactile feedback. Therefore, it may be difficult for the user to tell whether the touchscreen was properly pressed or not.
Therefore, among other deficiencies, the present art lacks an input device that is less confusing to the user. The present art also lacks input devices that are aesthetically pleasing while consuming less power.